Hydrotrim outside 90° is ideal for use with all outside corners. Also opens to a 135 degree corner or adjusts to any outside angle. Hydrotrim is an easy-to-apply corner that does not blister, bubble, dent or crack. Hydrotrim’s patent-pending design includes a water-activated adhesive and punch holes that allow joint compound to further bond the corner to the drywall. Fast and easy to apply – simple spray with water, press on. No screws, staples or messy adhesive spray needed. Water-activated adhesive creates an indestructible bond to drywall; perforated holes allow joint compound to permanently seal corner to wall.